Local Atomic Arrangements in Alloys and Intermetallics

使用复杂的x射线散射技术检查了相干应变在相形成中的作用。相形成的初始阶段包括局部有序区域或团簇的形成。相干应变可以影响这些团簇的组成并改变相图。通过测量镍钒合金体系的晶格参数，监测基体组成和析出相组成随体成分和温度的变化。预计相干应变在确定表面偏析方面起作用。在铜金、Cu3Au中，对晶体表面附近的局部秩序进行了检查，并与本体进行了比较。这项研究提供了对影响材料表面和整体微观结构和性能的因素的更深入的了解。

The role of coherency strains in phase formation is examined using sophisticated X-ray scattering techniques. The initial stages of phase formation involve formation of locally ordered regions or clusters. Coherency strains can affect the compositions of these clusters and modify the phase diagram. Lattice parameters are measured in the nickel-vanadium alloy system to monitor matrix composition and precipitate composition as a function of bulk composition and temperature. Coherency strains are expected to have a role in determining surface segregation. Local order near crystallographic surfaces is examined in copper-gold, Cu3Au, and compared to the bulk. %%% This research provides greater understanding of the factors that influence the surface and bulk microstructure and properties of materials.